$ ./ffmpeg
x265 [warning]: Unable to open libx265_main10.dll
ffmpeg version N-72228-gb8e7f2b Copyright (c) 2000-2015 the FFmpeg developers
  built with gcc 4.9.2 (Rev5, Built by MSYS2 project)
  configuration: --enable-gpl --enable-nonfree --enable-libdcadec --enable-libfdk-aac --enable-libmp3lame --enable-libopus --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-openssl --enable-opengl --disable-decoder=dca --target-os=mingw32 --arch=x86_64 --cc='ccache gcc' --cpu=amdfam10 --extra-cflags='-D_WIN32_WINNT=0x0600' --prefix=/mingw64
  libavutil      54. 23.101 / 54. 23.101
  libavcodec     56. 39.101 / 56. 39.101
  libavformat    56. 33.101 / 56. 33.101
  libavdevice    56.  4.100 / 56.  4.100
  libavfilter     5. 16.101 /  5. 16.101
  libswscale      3.  1.101 /  3.  1.101
  libswresample   1.  1.100 /  1.  1.100
  libpostproc    53.  3.100 / 53.  3.100
Hyper fast Audio and Video encoder
usage: ffmpeg [options] [[infile options] -i infile]... {[outfile options] outfile}...

Use -h to get full help or, even better, run 'man ffmpeg'